Search Results (72)

An ultrasonic-enhanced hydrogen peroxide water-washing process was developed to recover lead from raw flue dust (RFD) under neutral conditions. At optimal parameters (40 °C, 30 min, 4 mL H₂O₂, liquid-to-solid ratio 2:1, 240 W ultrasound), the Pb mass fraction in the solid residue increased from 41.68% in the RFD to 68.11%, accompanied by a Pb recovery rate of 97.1%. These values are significantly higher than those obtained under identical conditions without ultrasound (64.07% and 95.93%, respectively). Ultrasound promotes de-agglomeration and generates •OH radicals that accelerate the oxidation of PbSO₃ to insoluble PbSO₄ while concurrently removing impurity cadmium. This research offers a green and efficient alternative to traditional lead recovery methods, fostering sustainable development in the metallurgical industry. Full article

The Barcelona Raman LIDAR (BRL) will provide continuous monitoring of the aerosol extinction profile along the line of sight of the Cherenkov Telescope Array Observatory (CTAO). It will be located at its Northern site (CTAO-N) on the Observatorio del Roque de Los Muchachos. This article presents the performance of the pathfinder Barcelona Raman LIDAR (pBRL), a prototype instrument for the final BRL. Power budget simulations were carried out for the pBRL operating under various conditions, including clear nights, moon conditions, and dust intrusions. The LIDAR PreProcessing (LPP) software suite is presented, which includes several new statistical methods for background subtraction, signal gluing, ground layer and cloud detection and inversion, based on two elastic and one Raman lines. Preliminary test campaigns were conducted, first close to Barcelona and later at CTAO-N, albeit during moonlit nights only. The pBRL, under these non-optimal conditions, achieves maximum ranges up to about 35 km, range resolution of about 50 m for strongly absorbing dust layers, and 500 m for optically thin clouds with the Raman channel only, leading to similar resolutions for the LIDAR ratios and Ångström exponents. Given the reasonable agreement between the extinction coefficients obtained from the Raman and elastic lines independently, an accuracy of aerosol optical depth retrieval in the order of 0.05 can be assumed with the current setup. The results show that the pBRL can provide valuable scientific results on aerosol characteristics and structure, although not all performance requirements could be validated under the conditions found at the two test sites. Several moderate hardware improvements are planned for its final upgraded version, such as gated PMTs for the elastic channels and a reduced-power laser with a higher repetition rate, to ensure that the data acquisition system is not saturated and therefore not affected by residual ringing. Full article

Northeast China, a traditional heavy industrial base, faces significant carbon emissions challenges. This study analyzes the drivers of carbon emissions in 35 cities from 2000–2022, utilizing a machine-learning approach based on a stacking model. A stacking model, integrating random forest and eXtreme Gradient Boosting (XGBoost) as base learners and a support vector machine (SVM) as the meta-model, outperformed individual algorithms, achieving a coefficient of determination (R²) of 0.82. Compared to traditional methods, the stacking model significantly improves prediction accuracy and stability by combining the strengths of multiple algorithms. The Shapley additive explanations (SHAP) analysis identified key drivers: total energy consumption, urbanization rate, electricity consumption, and population positively influenced emissions, while sulfur dioxide (SO₂) emissions, smoke dust emissions, average temperature, and average humidity showed negative correlations. Notably, green coverage exhibited a complex, slightly positive relationship with emissions. Monte Carlo simulations of three scenarios (Baseline Scenario (BS), Aggressive De-coal Scenario (ADS), and Climate Resilience Scenario (CRS)) the projected carbon peak by 2030 under the ADS, with the lowest emissions fluctuation (standard deviation of 5) and the largest carbon emissions reduction (17.5–24.6%). The Baseline and Climate Resilience scenarios indicated a peak around 2039–2040. These findings suggest the important role of de-coalization. Targeted policy recommendations emphasize accelerating energy transition, promoting low-carbon industrial transformation, fostering green urbanization, and enhancing carbon sequestration to support Northeast China’s sustainable development and the achievement of dual-carbon goals. Full article

This paper presents the dedusting systems of a wheat mill in SC Agro Chirnogi, located in the southeastern area of Romania, and the physical characteristics of the material at the inlet, specifically at the base of the bagfilter systems. Samples were taken from both the dust removal system of the wheat cleaning technological phase (before milling) and from the dust removal system of the mill itself. It was found that the average particle size of the material at the cleaning section filter is between 1.191 and 0.563 mm, and the particle size of the material at the grinding section filter is between 0.278 and 0.186 mm, with their particle size distribution mainly following an exponential Rosin–Rammler distribution. Also, the bulk density of the material in the two bag filters ranges between 401 and 667 kg/m³ at the inlet and between 452 and 632 kg/m³ at the outlet of the cleaning technological phase filter. At the mill grinding section filter, the bulk density was between 426 and 506 kg/m³ at the inlet and between 422 and 580 kg/m³ at the outlet. The density of the material was between 854 and 1282 kg/m³ for the last fractions at the exit of the cleaning section filter and between 1309 and 1323 kg/m³ at the grinding section filter. Determinations were also made for other characteristics. Full article

Spain exhibits significant climatic variability across its regions, ranging from the humid oceanic climate in the north to the Mediterranean and stepped climates in the southern and central areas. These climatic differences influence environmental allergen exposure, which may, in turn, affect allergic sensitization patterns in the pediatric population. Variations in temperature, humidity, and airborne allergen distribution, such as pollen, dust mites, animal epithelia, and mold, contribute to regional disparities in allergic responses among children. Understanding how climatic conditions shape allergen recognition patterns across different geographical areas is essential for improving allergy prevention and management strategies. This study aims to shed light on this issue by identifying sensitization patterns in a pediatric population of 236 patients (with 2 age groups analyzed: 6–10 and 11–15 years old) from different climatic regions of Spain. Skin tests with standard aeroallergens were performed, and specific IgE (sIgE) analysis by Allergy Explorer of Macroarray Diagnostic test (ALEX²) and Western blot. The results revealed different sensitization trends across patients from the eight cities analyzed (Barcelona, Granada, Lugo, Sagunto, Santiago de Compostela, Valencia, and Zaragoza). Full article

The article presents the physico-mechanical properties of cement mortars modified with the addition of fly ash generated from municipal waste incineration (MSWI-FA) and dust from rotary kiln dedusting installations (CKD—cement kiln dust) produced during cement manufacturing. The waste materials were dosed separately and in combination—MSWI-FA in amounts of 10, 15, and 20% of the cement mass, with a volumetric adjustment of the standard sand mass, while CKD was used as a cement replacement in amounts of 10, 15, and 20% of the cement mass. Basic tests were conducted on the prepared mortars, including consistency and flexural and compressive strength after 7 and 28 days of curing, water absorption, bulk density, and resistance to freeze–thaw cycles. The results indicate that the addition of MSWI-FA and CKD reduces the strength of mortars compared to the control series, with CKD proving to be more effective and stable than MSWI-FA, especially over longer curing periods. The combination of MSWI-FA and CKD often resulted in the greatest decline in mechanical parameters, suggesting limited synergy between these materials. The best results were achieved using low additive concentrations, especially in the MSWI-FA-CKD/3–3 (i.e., after 3% of the MSWI-FA and CKD waste) combination. The research confirms the potential of utilizing MSWI-FA and CKD in sustainable cement compositions but highlights the need for further work on optimizing proportions and modification techniques. The importance of these efforts for reducing environmental impact and promoting a circular economy is emphasized. Full article

A one-year observation campaign from December 2020 to December 2021 was carried out in Jinan, a city that previously suffered from severe fine particulate matter (PM_2.5) pollution. The meteorological parameters and ambient concentrations of the air pollutants were recorded, and PM_2.5 samples were collected during the campaign. The inorganic chemical compositions of the PM_2.5 samples were measured, identifying 8 water-soluble ions (WSIs) and 15 trace metals. Pollution events, including 7 dust events (DEs) and 19 secondary inorganic events (SIEs), were identified and classified. The inorganic chemical compositions of the pollution events were characterized, summarized, and concluded. The low ratio of WSIs to PM_2.5, high concentrations of Ca²⁺ and Mg²⁺, and significant increases in trace metals were the dominant characteristics of PM_2.5 during DEs. The high concentrations of SO₄²⁻, NO₃⁻, and NH₄⁺; the high ratio of secondary ions to WSIs; and the high ratio of WSIs to PM_2.5 were the dominant characteristics of PM_2.5 during SIEs. Even though, recently, the PM_2.5 pollution in Jinan has not been as severe as pollution from a dozen years ago, it still exists, just at lower frequencies and pollution levels. This investigation provides the characteristics of PM_2.5 pollution under dramatically improved conditions and various ideas for the management and control of PM_2.5 pollution. Full article

The modern metallurgical industry produces approximately 90% of the volume of all produced steel; for this, integrated technology based on fossil materials such as coal, fluxes, and especially iron ore is used. This industry generates large amounts of waste and by-products at almost all stages of production. Alternative iron and steel production technologies based on iron ore, methane, or pure hydrogen are also not waste-free. To ensure sustainable waste management, efforts are made to seal processes as well as capture and recycle dusty waste. This work presents the results of research on the processing of sludge resulting from the dedusting of the basic oxygen furnace (BOF) process and landfilling in a lagoon. The work discusses the treatment of fine dusty sludge hydrated to 26–60% H₂O, to which various amounts of caking agents were added; also discussed are the rheological characteristics of the tested suspension systems, the possibility of forming these systems into larger fractions, and rapid drying using 100–600 W microwaves with a drying time of 1–9 min. The aim was to identify, describe, and characterize the parameters of the agglomeration process and obtain a product that was durable enough to transport and dose into slag baths in order to reduce iron oxides in liquid phases. During the research, completely dried briquettes with an appropriate strength were obtained. The study demonstrates that microwave drying at 300 W for 6 min achieved complete drying with a weight loss of 35%, whereas a higher-power treatment at 750 W for 2 min enhanced compressive strength by up to 95% and reached 15 N/psc, which was comparable with green iron ore pellets. This approach offers a sustainable alternative to traditional methods, but with a reduced drying time. Full article

The rise of the global tea industry market, influenced by the growing demands for healthier diet options, resulted in the constant increase in herbal tea production. In accordance, increased production leads to increased waste generation, especially in the area of filter tea production, which generates waste in the form of powdered plant material with particle sizes lower than 0.315 mm. The generated amount of this powdered plant material, also called herbal dust, can vary in the range from 10 to 40% of the total processed plant, and it is often considered waste only due to its size. Therefore, within this study, ultrasound-assisted extraction (UAE) was utilized for the extraction of green tea (Camellia sinensis L.), lemon balm (Melissa officinalis L.), and hibiscus (Hibiscus sabdariffa L.) herbal dust, and the quality of the obtained extracts was evaluated in terms of total phenolic content (TPC) and phenolic profile. In addition, UAE was conducted on the three different amplitudes (20, 60, and 100%) and two different extraction times (5 and 10 min) in order to investigate and compare the influence of different extraction parameters. The results showed that the maximum TPC for green tea, hibiscus, and lemon balm herbal dust was 152.91 ± 0.74, 60.63 ± 0.10, and 356.22 ± 3.13 mg GAE/g DE, respectively. HPLC analysis conducted for all of the obtained extracts confirmed the presence of several phenolic compounds, with the highest concentrations of epigallocatechin gallate (EGCG) for the extracts of green tea, and neochlorogenic acid for hibiscus herbal dust extracts. The HPLC analysis of the lemon balm extracts recorded the highest concentration of rosmarinic acid for all of the UAE conditions. The results reported within this study indicate that previously considered waste, herbal dust plant material can be successfully extracted by application of UAE and that the obtained extracts exhibit concentrations of bioactive compounds comparable to the extracts of the commercially available plant material. Full article

Ground-based observations of Very High Energy (VHE) gamma rays from extreme astrophysical sources are significantly influenced by atmospheric conditions. This is due to the atmosphere being an integral part of the detector when utilizing Imaging Atmospheric Cherenkov Telescopes (IACTs). Clouds and dust particles diminish atmospheric transmission of Cherenkov light, thereby impacting the reconstruction of the air showers and consequently the reconstructed gamma-ray spectra. Precise measurements of atmospheric transmission above Cherenkov observatories play a pivotal role in the accuracy of the analysed data, among which the corrections of the reconstructed energies and fluxes of incoming gamma rays, and in establishing observation strategies for different types of gamma-ray emitting sources. The Major Atmospheric Gamma Imaging Cherenkov (MAGIC) telescopes and the Cherenkov Telescope Array Observatory (CTAO), both located on the Observatorio del Roque de los Muchachos (ORM), La Palma, Canary Islands, use different sets of auxiliary instruments for real-time characterisation of the atmosphere. In this paper, historical data taken by MAGIC LIDAR (LIght Detection And Ranging) and CTAO FRAM (F/Photometric Robotic Telescope) are presented. From the atmospheric aerosol transmission profiles measured by the MAGIC LIDAR and CTAO FRAM aerosol optical depth maps, we obtain the characterisation of the clouds above the ORM at La Palma needed for data correction and optimal observation scheduling. Full article

Wet scrubbers are traditionally used as dedusting systems in waste incineration plants for wet flue gas treatment. Although these devices are not particularly performant at capturing submicron particles, which are associated with health and environmental hazards, their collection efficiency can be improved by optimizing operating conditions. This study presents the design methodology of a downscaled wet scrubber, constructed and implemented at a municipal waste incineration plant to be fed with real fumes, and to study its efficiency towards the removal of submicronic particles. The downscaled scrubber was designed to operate with flue gas at 200 °C, high humidity (1% RH), and an average total particle concentration of 200 mg/Nm³. A criterion of geometric, aerodynamic, and residence time similarities to an existing industrial scrubber was targeted. The height of the device was selected by matching the theoretical fractional particle collection efficiencies of the industrial and downscaled scrubbers. Featuring a cylindrical shape, the downscaled scrubber has a diameter of 0.3 m and a height of 2.5 m. It operates in co-current with water injected through four spray levels. Computational fluid dynamics simulations were conducted to analyze the gas flow structure within the device, and the results were validated by hot wire anemometer velocity measurements. Full article

Updated notions about the so-called hygiene hypothesis consider now that helminths may have influence in the training of the immune system during childhood. Considering the similar type of immune response between helminth infections and allergic illnesses, the objective of this study was to evaluate how structural and functional conservation between house-dust mite allergens and their helminth orthologs might contribute to the cross-induction of IgE responses in allergies and helminthiasis. Amino acid sequences from group-1, -2, -5, -9, -10, -18, -21, and -23 allergens of the house dust mite Dermatophagoides pteronyssinus were retrieved from curated databases, and orthologs were identified in other mite species and different helminth parasites. We also assessed structural, conservational, functional, and immunologic relationships between these major mite allergens and their helminth counterparts. De novo 3D-modelling, B-cell epitopes prediction, structural conservation, and docking analyses were analyzed by Robetta platform, ElliPro and CBTope, RaptorX, and Z-Dock, respectively. Our results extend previous findings on structural conservations between major allergens and parasite proteins and show that these conservations go beyond the well-known conservations and may account for the observed immunological cross-reactions. This understanding can contribute in the near future to the development of more specific serological testing for mite-induced allergies and helminthiasis. Full article

Dust deposition is an important aspect of the conservation of heritage collections. Most proposed methods for dust monitoring focus on total area coverage or airborne concentrations. There is a lack of published data and methodologies to obtain size distributions of deposited particles on real historic sites. The purpose of the study was to develop and describe a method for obtaining quantitative data from dust deposition without the need for sophisticated laboratory equipment, based on optical microscopy photography and software-based image analysis. Bare microscope slides were used as passive collectors of dust. Tests were carried out on a collection of oil paintings displayed in the cloister of the Monastery of Santa María de El Paular in the Sierra de Guadarrama in Spain for one year, with a distance of 100 km between this place and the laboratory. The designed method allowed for the detection of significant differences in deposition depending on the location and seasonal period. Vertically orientated bare slides did not provide relevant information and a magnification of 50× was not really useful. However, horizontal collectors and a magnification of 10× allowed studying the deposition of particles above 2 μm². Full article

China faces a challenge in the sustainable development of the coal industry due to pneumoconiosis problems. Dust control technologies are crucial for safe production and miners’ health, ensuring the industry’s longevity. This article reviews the development process of dust prevention and control in underground coal mines in China, summarizes various technologies, and divides them into dust suppression, open-space dust reduction, and mine dust collectors according to different stages and environments of use. In dust suppression technologies, coal-seam water injection can reduce total dust generation by 60%, wet rock drilling can reduce drilling dust in the presence of stable water sources and high-pressure bearing equipment, and water-seal blasting can reduce blasting dust by 50–70%. In open-space dust reduction technologies, spray dust suppression can remove total dust by 50–95% and the removal efficiencies of foam dedusting for total and respirable dust are reported to reach 95% and 85% under the right conditions, respectively. In dust collector technologies, dry collectors can remove 80–95% of total dust. Wet collectors achieve up to 90% efficiency, dependent on water supply and waste processing. This article also discusses vapor heterogeneous condensation technology as a promising method for improving respirable dust removal in humid mine environments. Full article

North Africa, the Middle East, and Europe (NAMEE domain) host a variety of suspended particles characterized by different optical and microphysical properties. In the current study, we investigate the importance of the lidar ratio (LR) on Cloud-Aerosol Lidar with Orthogonal Polarization–Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIOP-CALIPSO) aerosol retrievals towards assessing aerosols’ impact on the Earth-atmosphere radiation budget. A holistic approach has been adopted involving collocated Aerosol Robotic Network (AERONET) observations, Radiative Transfer Model (RTM) simulations, as well as reference radiation measurements acquired using spaceborne (Clouds and the Earth’s Radiant Energy System-CERES) and ground-based (Baseline Surface Radiation Network-BSRN) instruments. We are assessing the clear-sky shortwave (SW) direct radiative effects (DREs) on 550 atmospheric scenes, identified within the 2007–2020 period, in which the primary tropospheric aerosol species (dust, marine, polluted continental/smoke, elevated smoke, and clean continental) are probed using CALIPSO. RTM runs have been performed relying on CALIOP retrievals in which the default and the DeLiAn (Depolarization ratio, Lidar ratio, and Ångström exponent)-based aerosol-speciated LRs are considered. The simulated fields from both configurations are compared against those produced when AERONET AODs are applied. Overall, the DeLiAn LRs leads to better results mainly when mineral particles are either solely recorded or coexist with other aerosol species (e.g., sea-salt). In quantitative terms, the errors in DREs are reduced by ~26–27% at the surface (from 5.3 to 3.9 W/m²) and within the atmosphere (from −3.3 to −2.4 W/m²). The improvements become more significant (reaching up to ~35%) for moderate-to-high aerosol loads (AOD ≥ 0.2). Full article